Diethanolamine, often abbreviated as DEA, is an organic chemical compound which is both a secondary amine and a dialcohol. A dialcohol has two hydroxyl groups in its molecule. Like other amines, diethanolamine acts as a weak base. Diethanolamine is widely used in the preparation of diethanolamides and diethanolamine salts of long-chain fatty acids that are formulated into soaps and surfactants used in liquid laundry and dishwashing detergents, cosmetics, shampoos, and hair conditioners. Diethanolamine is also used in textile processing, in industrial gas purification to remove acid gases, as an anticorrosion agent in metalworking fluids, and in preparations of agricultural chemicals. Aqueous diethanolamine solutions are used as solvents for numerous drugs that are administered intravenously.

This compound belongs to the class of organic compounds known as 1,2-aminoalcohols. These are organic compounds containing an alkyl chain with an amine group bound to the C1 atom and an alcohol group bound to the C2 atom.

Peschel, Werner; Hildebrandt, Axel; Bessling, Bernd. Continuous process for the synthesis of monoethanolamine, diethanolamine and triethanolamine via the addition reaction of ammonia with ethylene oxide in the presence of water as a catalyst. Eur. Pat. Appl. (2003), 11 pp.